League leaders Dundee United failed to score for the fourth time in five Ladbrokes Championship games as they drew 0-0 at Ayr.
The Tangerines have now won just one of their last six games but still have a 16-point lead over second-placed Inverness.
Ayr striker Stephen Kelly, on loan from Rangers, had a good chance to put the home side ahead in the first half but fired wide.
Ian Harkes had one of Dundee United's best opportunities after the break but he failed to find the target as both sides settled for a share of the spoils.